Bridge for junction boxes



BRIDGE FOR JUNCTION BOXES Filed Nov. 4, 1947 F; EL 20 IO INVENTOR. HENRYKERSHAW ATTORNEY Patented Oct. 12, 1948 UNITED STATES PATENT OFFICE 4Claims.

My invention relates to improvements in metallic bridges for junctionboxes, shown in my Patent 2,427,285.

An important object of the invention is to pro vide means to eliminatethe soldering of the wires to the bridge, while effecting a firmelectrical contact or engagement between the wire and bridge.

A further object of the invention is to provide a clamping element orplate to be interlocked with the bridge.

A further object of the invention is to provide a device of the abovementioned character which is simple in construction, cheap tomanufacture, and easy to assemble.

In accompanying drawings forming a part of this application, and inwhich like numerals are employed to designate like parts throughout thesame,

Figure 1 is a plan view of the assembled bridge device and insulatingcovering,

Figure 2 is a plan view of the assembled bridge device, the insulatingcovering being removed,

Figure 3 is a bottom plan view of the same,

Figure 4 is a transverse section taken on line 4-4, Figure 2, and,

Figure 5 is an exploded perspective view of the insulated bridge device.

In the drawings, wherein for the purpose of illustration is shown apreferred embodiment of my invention, the numeral I0 designates abridge, included in the bridge device, This bridge is preferably flatand is preferably formed of sheet copper having a suitably lowresistance to properly carry the load without liability of overheatingat the connections. The bridge is preferably polygonal, being formedfrom a square, with its corners cut off at I I. This bridge III haspairs of lugs or cars 12 stamped therefrom forming openings I3. Thesepairs of lugs are disposed upon the same face of the bridge I 0 and thepairs of lugs are equidistantly spaced radially from the center of thebridge Ill.

Adapted for coaction with the bridge I0 is a clamping element or plateI4, also preferably formed of copper having suitably low resistance toproperly carry the load without liability of overheating at theconnections. This plate I4 is preferably flat and is slightly elongatedand is provided at its ends with depending arms I 5, bent downwardly atI6. At its ends adjacent to the arms I5, the flat plate has notches I!and the edges I 8 of these notches are spaced apart for a distance equalto the distance between the longitudinal edges IQ of the plate I4, Theopposed pair of bent down lugs I2.

pairs of lugs I2 are spaced apart for a slightly greater distance thanthe opposed edges I8 and the opposed edges I9.

The numeral 20 designates pairs of wires hav ing the insulation strippedfrom their ends, and the ends of these wires are bent at right angles,as shown.

In use, the bent ends of the pairs of wires are arranged between thelugs I2 in adjacent pairs, Figure 2, and these lugs I2 are then bentdown over the wires for clamping engagement there? with. Two pairs ofwires are shown thus applied to the bridge III. The clamping element Itis now arranged above the bridge Ill and its arms I5 passed through theopenings 39 in the opposed pair of such openings. The arms I5 extendoutwardly of and upon the sides of the adjacent bent down pairs of lugsI 2 and these bent down pairs of lugs pass into the notches I'.', andthe edges I3 are arranged inwardly of these lugs. The edges I9 arearranged inwardly of the remaining Since the distance between the edgesI8 is equal to the distance between the edges I9, the clamping elementor plate I 4 may be applied to the bridge Io at right angles to itsposition shown in Figure 2, if desired. After the clamping element orplate I4 is thus applied to the bridge I0, Figure 3, the arms I5 arebent downwardly inwardly over the bridge [I], as shown. The clampingelement or plate I4 and bridge II are subjected to a squeezing action bypliers or the like, so that these opposed elements will securely clampthe inner portion of the folded ends of the wires 20 between them. It isthus seen that the clamping element or plate serves to securely bind thewires to the bridge Ill and effects the firm electrical contact orengagement between the wires and the bridge, eliminating the use ofsoldering, and further stiifening and strengthening the bridge at itscenter. After the elements are thus assembled, insulating sheets 2| areapplied to the opposite faces of the bridge I0 and project radiallyoutwardly beyond the bridge. These insulating sheets may be formed ofasbestos or the like and have their inner faces coated with an adhesive,so that they may be readily bonded to the bridge and clamping element I4and to themselves at their outer marginal edges.

While I have shown the wires 20 arranged in pairs, with their ends bentat right angles, yet the invention is not restricted to thisarrangement, as the same may be varied, as shown in my Patent 2,427,285.

The bridges I 0 and clamping elements I4 are assembled exteriorly of thejunction box, and these assembled units are subsequently arranged in thejunction box. The arrangement is like that shown in Patent 2,427,285,two or three units being employed, as desired.

Having thus described my invention, what I claim is:

1. A bridge for connecting a plurality of wires, said bridge beingformed of conducting material and including a face and having pairs oflugs stamped therefrom forming openings adjacent to the lugs, the endsof the wires being adapted to be passed between the lugs in the pairsand the lugs bent over the wires, and a clamping element to engage theends of the Wires inwardly of the lugs and formed of conducting materialand having arms for insertion through certain of the openings in thebridge, said arms being adapted to be bent over the face of the bridge.

2. A bridge for connecting a plurality of wires, said bridge beingformed of conducting material and including a face and having lugsstamped therefrom forming openings adjacent to the lugs, the ends of thewires being adapted to be arranged upon the face of the bridge and thelugs bent over the same, and a plate formed of conducting material tocover the ends of the wires and having arms to be extended throughcertain of the penings for interlocking engagement with the bridge.

3. A substantially flat bridge for connecting a plurality of wires, saidbridge being formed of conducting material and having pairs of lugsstamped therefrom and arranged upon the same face of the bridge, saidstamped lugs forming openings, the ends of the wires being adapted to bearranged between the lugs in the pairs and the lugs bent over such ends,and a substantially flat plate formed of conducting material to coverthe 4 ends of the wires and having pairs of latterly extending arms forinsertion within certain openings, the ends of the arms being adapted tobe bent over the face of the plate remote from the lugs.

4. A bridge device for connecting wires, comprising a bridge formed ofconducting material and including faces and having pairs of lugs stampedtherefrom and arranged upon the same face of the bridge and formingopenings, the pairs of lugs being substantially equidistantly spacedfrom the center of the bridge, and a coacting plate formed of conductingmaterial and including faces, the plate being adapted to cover the endsof the wire and provided at its ends with pairs of laterally extendingarms disposed upon the same face of the plate for insertion throughcertain of the openings of the bridge, the coacting plate having notchesbetween the armsto receive inner portions of the pairs of lugs, thedistance between the notches and the distance between the side edges ofthe coacting plate being less than the distance between the inner endsof opposed pairs of lugs.

HENRY KERSHAW.

REFERENCES CITED The following references are of record in the file ofthis patent:

UNITED STATES PATENTS Number Name Date 1,055,305 Kneisel Mar. 4, 19131,225,366 Schoenman May i912 FOREIGN PATENTS Number Country Date 340,671Great Britain Jan. 8, 1931

